In packet communication networks, latency arises on a connection as a result of the finite travel time of packets from one end of the connection to the other end. In real time applications, such as voice calls or videoconferencing, it is important to minimize the latency of the connection in order that the end users perceive as little delay as possible in traffic. Minimization of latency is less important for non-real time applications, such as e-mail, but is usually desirable.
In applications involving multiple users, such as multi-player network gaming, differences in latency between the connections of each user can have an impact on the application. For example, in a multiple-player network game requiring simultaneous actions by the players interacting in a shared virtual world, a player whose connection has a latency lower than that of the other players may provide an unfair advantage, as the player is informed of changes in the virtual world ahead of other players, and is able to react to those changes before other players can do so.
While reducing latency in multi-user applications remains important, in some applications it may be still more important to ensure that the latency of each user is equalized. A system which equalized latency of multiple users would allow such applications to run more effectively and, in the case of network gaming, more fairly.